Neoplastic precursor lesions in Barrett's esophagus.

Barrett's esophagus, currently defined as endoscopically apparent columnar metaplasia of the esophagus with histologic documentation of goblet cells, is the precursor to esophageal adenocarcinoma. However, not all patients with this disorder require intensive surveillance. Pathologic diagnosis and grading of dysplasia in mucosal biopsies remains the best and most widely used method of determining which patients are at highest risk for neoplastic progression. The task of diagnosing dysplasia suffers from considerable interobserver variability. Therefore, consultation with expert gastrointestinal pathologists to confirm the diagnosis of dysplasia before definitive management is highly advisable. Adjunctive methods to improve reproducibility, such as immunostaining for alpha-methylacyl-CoA racemase, show promise but require confirmation in larger studies. This article focuses on dysplasia in Barrett's esophagus in terms of its classification, pathologic diagnostic criteria, limitations, natural history, and treatment.